ACDelco RC98 15 P.S.I. Radiator Surge Tank Cap - GM Original Equipment Review

I was having trouble with my 2002 Gmc Sierra 1500 SLE with a 4.8L V8 that was losing coolant. I thought I might have a very small leak in the fitting which could be incredibly frustrating. I had to fill up the tank every three months, so I decided to play this cap cheaply. I'm happy to say that was a year ago and I haven't had to fill up my tank since.

Like a few other reviewers, I had an unexplained coolant leak on my 2005 Cadillac SRX with no visible leaks. Some research has shown this to be a common problem on GM vehicles where the o-rings in the stock radiator cap wear out and coolant leaks from the overflow vent tube. I replaced the cap, it seems to be OEM ACdelco, the problem is solved.

There was a coolant reservoir that was constantly dripping. I took a chance and replaced the lid, it wasn't even the old lid. I'm assuming the O-ring was leaking. So there is no coolant leak or seal failure on my LQ4, which is nice. FYI if it's confusing why it's being caused by a leaking radiator cap. Note that the boiling point of water (212F at normal pressure) increases with pressure. Relieve the pressure and you can slowly boil off the water in the cooling system, it can be very slow to…

There was a coolant reservoir that kept dripping. I took a chance and replaced the lid, it wasn't even the old lid. I suspect the o-ring was leaking. So there is no coolant leak or seal failure on my LQ4, which is nice. FYI if it's confusing why it's being caused by a leaking radiator cap. Note that the boiling point of water (212F at normal pressure) increases with pressure. Relieve the pressure and you can slowly boil off the water in the cooling system, it can be very slow to never notice.

My 2000 Malibu with GM 3.1 V6 was losing coolant. I've gone through all sorts of checks and tests and figured the problem might be a bad head gasket or something more expensive. I did not look at the coolant cap as I recently replaced the expansion tank and cap with a non-original unit. Looking at the aftermarket cap, I actually saw damage to the bottom o-ring. As soon as I put that on, the coolant leak stopped and the expansion tank stopped overflowing. The bottom o-ring appears to be more…

First, this is an OEM part. That's what the manufacturer specified for my 2005 Silverado. Second, it is reasonably priced. Like many, I had the problem of coolant loss. Add coolant and after a few short cold/warm cycles (riding and then letting cool overnight, riding again) my coolant level started to drop. Top up again, drive a few times and the level will drop. After 25,000 km, the situation gradually worsened. When the problem first started I drove about 1200-1500 miles before the coolant…